net/sched: em_text: reject unterminated algo before autoload
In the Linux kernel, the following vulnerability has been resolved: net/sched: em_text: reject unterminated algo before autoload This is a follow-up to commit 9c572a83037a ("net/sched: fix potential stack infoleak in em_text_dump()"), which zero-initialised the dump-side struct. Sashiko pointed at a pre-existing bug that exposed the change-side input-validation gap open. em_text_change() casts the raw netlink attribute payload to struct tcf_em_text and passes conf->algo, a 16-byte array with no enforced NUL terminator, to textsearch_prepare(). On the TS_AUTOLOAD retry textsearch_prepare() calls request_module("ts_%s", algo); vsnprintf() walks %s until it finds a NUL, so an algo[] with no NUL reads past the array into the adjacent struct fields and payload and feeds those bytes to the usermode helper command line. This is an out-of-bounds read and a kernel memory disclosure. Reject the attribute when no NUL exists within TC_EM_TEXT_ALGOSIZ bytes, matching the check xt_string has had since 3ab720881b6e. Conditions to recreate the bug: - CAP_NET_ADMIN on the target netns (namespace-local via unshare -Urn is enough) - install clsact on an interface, then add a basic filter with one text ematch whose algo[] is 16 bytes with no NUL (e.g. "A"*16) and pattern_len at least 1 - the add fails with -ENOENT and the kernel invokes modprobe with a module name made of "ts_" plus the 16 bytes and the adjacent payload
CVE-2026-98969
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98969
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "d675c989ed2d4ba23dff615330b04371aea83534",
"lessThan": "00bcc303000bac524d62eed054d77372b38ace0f",
"versionType": "git"
},
{
"status": "affected",
"version": "d675c989ed2d4ba23dff615330b04371aea83534",
"lessThan": "22182f91c6703af6e9832cffe6d22b381031cb5a",
"versionType": "git"
},
{
"status": "affected",
"version": "d675c989ed2d4ba23dff615330b04371aea83534",
"lessThan": "85e5512369d4fe6e5f2c43712d9f9e01d4ae8437",
"versionType": "git"
},
{
"status": "affected",
"version": "d675c989ed2d4ba23dff615330b04371aea83534",
"lessThan": "b627c6ba20be20334338229b4820baacb9d96826",
"versionType": "git"
},
{
"status": "affected",
"version": "d675c989ed2d4ba23dff615330b04371aea83534",
"lessThan": "c9728fcf2e7fb4a7a8d08ebd9524c3b02ae1a021",
"versionType": "git"
}
],
"programFiles": [
"net/sched/em_text.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.57",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.11",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sched/em_text.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98969
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #52825 · Revision 1
- Added to Heist Feed
- Publisher date